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1.
RSC Chem Biol ; 5(7): 652-668, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38966670

RESUMO

Bacterial ribonuclease P (RNase P) is a tRNA processing endonuclease that occurs primarily as a ribonucleoprotein with a catalytic RNA subunit (P RNA). As one of the first ribozymes discovered, P RNA is a well-studied model system for understanding RNA catalysis and substrate recognition. Extensive structural and biochemical studies have revealed the structure of RNase P bound to precursor tRNA (ptRNA) and product tRNA. These studies also helped to define active site residues and propose the molecular interactions that are involved in substrate binding and catalysis. However, a detailed quantitative model of the reaction cycle that includes the structures of intermediates and the process of positioning active site metal ions for catalysis is lacking. To further this goal, we used a chemically modified minimal RNA duplex substrate (MD1) to establish a kinetic framework for measuring the functional effects of P RNA active site mutations. Substitution of U69, a critical nucleotide involved in active site Mg2+ binding, was found to reduce catalysis >500-fold as expected, but had no measurable effect on ptRNA binding kinetics. In contrast, the same U69 mutations had little effect on catalysis in Ca2+ compared to reactions containing native Mg2+ ions. CryoEM structures and SHAPE mapping suggested increased flexibility of U69 and adjacent nucleotides in Ca2+ compared to Mg2+. These results support a model in which slow catalysis in Ca2+ is due to inability to engage U69. These studies establish a set of experimental tools to analyze RNase P kinetics and mechanism and can be expanded to gain new insights into the assembly of the active RNase P-ptRNA complex.

2.
Tuberculosis (Edinb) ; 148: 102541, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-39002312

RESUMO

Bovine tuberculosis (bTB), primarily caused by Mycobacterium bovis (M. bovis), is a globally zoonotic disease with significant economic impacts. Plasma exosomes have been extensively used for investigating disease processes and exploring biomarkers. While mass spectrometry (MS)-based proteomic analysis of plasma exosomes has been employed for human tuberculosis (TB) studies, it has not yet been applied to bTB. Therefore, a comprehensive proteomic overview of plasma exosomes from M. bovis-infected cows is essential. In this study, we presented an extensive proteomic analysis of plasma exosomes from 89 M. bovis-infected cows across three farms, using data dependent acquisition (DDA) mode. Our analysis encompasses 239,894 spectra, 6,011 peptides and 835 proteins. The proteomic overview revealed both consistencies and differences among individual cows, supplements 595 proteins to the bovine exosome library, and enriches tuberculosis and related pathways. Additionally, six pathways were validated as immune response pathways, and three proteins (CATHL1, H1-1, and LCN2) were identified as potential indicators of bTB. This study is the first to investigate the exosome proteome of plasma from cows infected with M. bovis, providing a valuable dataset for exploring candidate bTB markers and understanding the mechanisms of host defense against M. bovis.

3.
Cell Chem Biol ; 31(6): 1101-1117, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38876100

RESUMO

RNA-targeting small molecules (rSMs) have become an attractive modality to tackle traditionally undruggable proteins and expand the druggable space. Among many innovative concepts, RNA-targeting chimeras (RNATACs) represent a new class of multispecific, induced proximity small molecules that act by chemically bringing RNA targets into proximity with an endogenous RNA effector, such as a ribonuclease (RNase). Depending on the RNA effector, RNATACs can alter the stability, localization, translation, or splicing of the target RNA. Although still in its infancy, this new modality has the potential for broad applications in the future to treat diseases with high unmet need. In this review, we discuss potential advantages of RNATACs, recent progress in the field, and challenges to this cutting-edge technology.


Assuntos
RNA , Bibliotecas de Moléculas Pequenas , Humanos , RNA/metabolismo , RNA/química , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Ribonucleases/metabolismo
4.
J Speech Lang Hear Res ; 66(10): 4100-4116, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37678219

RESUMO

PURPOSE: This study aimed to examine the developmental trajectory of Mandarin tone identification in quiet and two noisy conditions: speech-shaped noise (SSN) and multitalker babble noise. In addition, we evaluated the relationship between tonal identification development and working memory capacity. METHOD: Ninety-three typically developing children aged 5-8 years and 23 young adults completed categorical identification of two tonal continua (Tone 1-4 and Tone 2-3) in quiet, SSN, and babble noise. Their working memory was additionally measured using auditory digit span tests. Correlation analyses between digit span scores and boundary widths were performed. RESULTS: Six-year-old children have achieved the adultlike ability of categorical identification of Tone 1-4 continuum under both types of noise. Moreover, 6-year-old children could identify Tone 2-3 continuum as well as adults in SSN. Nonetheless, the child participants, even 8-year-olds, performed worse when tokens from Tone 2-3 continuum were masked by babble noise. Greater working memory capacity was associated with better tone identification in noise for preschoolers aged 5-6 years; however, for school-age children aged 7-8 years, such correlation only existed in Tone 2-3 continuum in SSN. CONCLUSIONS: Lexical tone perception might take a prolonged time to achieve adultlike competence in babble noise relative to SSN. Moreover, a significant interaction between masking type and stimulus difficulty was found, as indicated by Tone 2-3 being more susceptible to interference from babble noise than Tone 1-4. Furthermore, correlations between working memory capacity and tone perception in noise varied with developmental stage, stimulus difficulty, and masking type.


Assuntos
Memória de Curto Prazo , Percepção da Fala , Criança , Adulto Jovem , Humanos , Ruído , Fala , Percepção do Timbre , Distúrbios da Fala
5.
J Speech Lang Hear Res ; 66(9): 3382-3398, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37647655

RESUMO

PURPOSE: Previous studies have shown that individuals who stutter exhibit abnormal speech perception in addition to disfluent production as compared with their nonstuttering peers. This study investigated whether adult Chinese-speaking stutterers are still able to use knowledge of statistical regularities embedded in their native language to recognize spoken words and, if so, how much acoustic information is needed to trigger this information. METHOD: Seventeen stutterers and 20 typical, nonstuttering controls participated in a gating experiment. All participants listened to monosyllabic words that consisted of syllables and lexical tones and were segmented into eight successive gates. These words differed in syllable token frequency and syllable-tone co-occurrence probability in line with a Chinese spoken word corpus. The correct syllable-only, correct tone-only, correct syllable-tone word, and correct syllable-incorrect tone responses were analyzed between the two groups using mixed-effects models. RESULTS: Stutterers were less accurate overall than controls, with fewer correct syllables, tones, and their combination as words. However, stutterers showed consistent and reliable perceptual patterns triggered by statistical information of speech, as reflected by more accurate responses to high-frequency syllables, high-probability tones, and tone errors all in manners similar to those of nonstuttering controls. CONCLUSIONS: Stutterers' atypical speech perception is not due to a lack of statistical learning. Stutterers were able to perceive spoken words with phonological tones based on statistical regularities embedded in their native speech. This finding echoes previous production studies of stuttering and lends some support for a link between perception and production. Implications of pathological, diagnostic, and therapeutic conditions of stuttering are discussed.


Assuntos
Gagueira , Adulto , Humanos , Idioma , Linguística , Fala , Acústica
6.
J Speech Lang Hear Res ; 66(7): 2461-2477, 2023 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-37267445

RESUMO

PURPOSE: Previous studies have shown that individuals with congenital amusia exhibit deficient pitch processing across music and language domains. This study investigated whether adult Chinese-speaking listeners with amusia were still able to learn Thai lexical tones based on stimulus frequency of statistical distribution via distributional learning, despite their degraded lexical tone perception. METHOD: Following a pretest-training-posttest design, 21 amusics and 23 typical, musically intact listeners were assigned into bimodal and unimodal distribution conditions. Listeners were asked to discriminate minimal pairs of Thai mid-level tone and falling tone superimposed on variable base syllables and uttered by different speakers. The perceptual accuracy for each test session and improvement from pretest to posttest were collected and analyzed between the two groups using generalized mixed-effects models. RESULTS: When discriminating Thai lexical tones, amusics were less accurate than typical listeners. Nonetheless, similarly to control listeners, perceptual gains from pretest to posttest were observed in bimodally rather than unimodally trained amusics, as evidenced by both trained and nontrained test words. CONCLUSIONS: Amusics are able to learn lexical tones in a second or foreign context of speech. This extends previous research by showing that amusics' distributional learning of linguistic pitch remains largely preserved despite their degraded pitch processing. It is thus likely that manifestations of amusia in speech could not result from their abnormal statistical learning mechanism. This study meanwhile provides a heuristic approach for future studies to apply this paradigm into amusics' treatment to mitigate their pitch-processing disorder.


Assuntos
Transtornos da Percepção Auditiva , Surdez , Música , Percepção da Fala , Adulto , Humanos , Percepção da Altura Sonora , Idioma , Transtornos da Percepção Auditiva/diagnóstico , Estimulação Acústica
7.
J Acoust Soc Am ; 153(5): 3117, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37232583

RESUMO

Congenital amusia is an innate and lifelong deficit of music processing. This study investigated whether adult listeners with amusia were still able to learn pitch-related musical chords based on stimulus frequency of statistical distribution, i.e., via distributional learning. Following a pretest-training-posttest design, 18 amusics and 19 typical, musically intact listeners were assigned to bimodal and unimodal conditions that differed in distribution of the stimuli. Participants' task was to discriminate chord minimal pairs, which were transposed to a novel microtonal scale. Accuracy rates for each test session were collected and compared between the two groups using generalized mixed-effects models. Results showed that amusics were less accurate than typical listeners at all comparisons, thus corroborating previous findings. Importantly, amusics-like typical listeners-demonstrated perceptual gains from pretest to posttest in the bimodal condition (but not the unimodal condition). The findings reveal that amusics' distributional learning of music remains largely preserved despite their deficient music processing. Implications of the results for statistical learning and intervention programs to mitigate amusia are discussed.


Assuntos
Transtornos da Percepção Auditiva , Surdez , Perda Auditiva , Música , Adulto , Humanos , Percepção da Altura Sonora , Estimulação Acústica , Aprendizagem , Transtornos da Percepção Auditiva/diagnóstico
8.
Genome Biol ; 24(1): 39, 2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36869394

RESUMO

Spatially resolved transcriptomics (SRT)-specific computational methods are often developed, tested, validated, and evaluated in silico using simulated data. Unfortunately, existing simulated SRT data are often poorly documented, hard to reproduce, or unrealistic. Single-cell simulators are not directly applicable for SRT simulation as they cannot incorporate spatial information. We present SRTsim, an SRT-specific simulator for scalable, reproducible, and realistic SRT simulations. SRTsim not only maintains various expression characteristics of SRT data but also preserves spatial patterns. We illustrate the benefits of SRTsim in benchmarking methods for spatial clustering, spatial expression pattern detection, and cell-cell communication identification.


Assuntos
Perfilação da Expressão Gênica , Transcriptoma , Benchmarking , Comunicação Celular , Simulação por Computador
9.
J Speech Lang Hear Res ; 65(11): 4469-4484, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36351247

RESUMO

PURPOSE: Previous research has indicated the beneficial effects of musical training on speech perception in children. However, little has been known about whether musical training exerts transfer effects on fine-grained perception of linguistic pitch and time information. This study aimed to investigate the effects of different musical training programs and training duration on preschoolers' categorical perception (CP) of lexical tones and voice onset time (VOT) in Mandarin Chinese, which utilize pitch and time changes, respectively, to convey phonemic contrasts. METHOD: Sixty-one Mandarin-speaking children aged 4 years were randomly assigned to pitch-based musical training (carillon group), rhythm-based musical training (drum group), or handcraft learning (control group). Children completed the tests designed to assess their musical abilities, CP of lexical tones and VOT, IQ, and working memory at three time-points. Repeated-measures analyses of variance were conducted to evaluate the training-related effects in various tasks. Correlation analyses were used to infer the relationships between musical abilities and CP performance of speech. RESULTS: The carillon group demonstrated advantages over the drum and control groups in music pitch processing and CP of lexical tones; besides, the drum group performed better in the music time processing and CP of VOT than the control group. Moreover, positive correlations were found between musical gains and improvements on CP of speech. CONCLUSIONS: These results provide evidence that transfer effects occur in CP of lexical tones and VOT in preschoolers. Our findings highlight the selectivity of musical advantages driven by different components of training programs and suggest that long-term musical training could be a means of early speech rehabilitation in children with communication disorders.


Assuntos
Música , Percepção da Fala , Criança , Humanos , Percepção da Altura Sonora , Fala , Idioma
10.
J Speech Lang Hear Res ; 65(11): 4385-4403, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36269618

RESUMO

PURPOSE: Armed with the theory of embodied cognition proposing tight interactions between perception, motor, and cognition, this study aimed to test the hypothesis that speech rate-altered Mandarin lexical tone perception in quiet and noisy environments could be affected by the bodily dynamic cross-modal information. METHOD: Fifty-three adult listeners completed a Mandarin tone perception task with 720 tone stimuli in auditory-only (AO), auditory-facial (AF), and auditory-facial-plus-gestural (AFG) modalities, at fast, normal, and slow speech rates under quiet and noisy conditions. In AF and AFG modalities, both congruent and incongruent audiovisual information were designed and presented. Generalized linear mixed-effects models were constructed to analyze the accuracy of tone perception across different conditions. RESULTS: In Mandarin tone perception, the magnitude of enhancement of AF and AFG cues across three speech rates was significantly higher than that of the AO cue in the adverse context of noise, yet additional metaphoric gestures did not show significant differences from the facial information. Furthermore, the performance of auditory tone perception at the fast speech rate was significantly better than that at the normal speech rate when the inputs were incongruent between auditory and visual channels in quiet. CONCLUSIONS: This study provided compelling evidence showing that integrated audiovisual information plays a vital role not only in improving lexical tone perception in noise but also in modulating the effects of speech rate on Mandarin tone perception in quiet for native listeners. Our findings, supporting the theory of embodied cognition, are implicational for speech and hearing rehabilitation among both young and old clinical populations.


Assuntos
Sinais (Psicologia) , Percepção da Fala , Adulto , Humanos , Fala , Ruído/efeitos adversos , Percepção do Timbre
11.
Cell Metab ; 34(9): 1359-1376.e7, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35973424

RESUMO

The mammalian liver comprises heterogeneous cell types within its tissue microenvironment that undergo pathophysiological reprogramming in disease states, such as non-alcoholic steatohepatitis (NASH). Patients with NASH are at an increased risk for the development of hepatocellular carcinoma (HCC). However, the molecular and cellular nature of liver microenvironment remodeling that links NASH to liver carcinogenesis remains obscure. Here, we show that diet-induced NASH is characterized by the induction of tumor-associated macrophage (TAM)-like macrophages and exhaustion of cytotoxic CD8+ T cells in the liver. The adipocyte-derived endocrine factor Neuregulin 4 (NRG4) serves as a hormonal checkpoint that restrains this pathological reprogramming during NASH. NRG4 deficiency exacerbated the induction of tumor-prone liver immune microenvironment and NASH-related HCC, whereas transgenic NRG4 overexpression elicited protective effects in mice. In a therapeutic setting, recombinant NRG4-Fc fusion protein exhibited remarkable potency in suppressing HCC and prolonged survival in the treated mice. These findings pave the way for therapeutic intervention of liver cancer by targeting the NRG4 hormonal checkpoint.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Neurregulinas/metabolismo , Hepatopatia Gordurosa não Alcoólica , Animais , Carcinoma Hepatocelular/metabolismo , Fígado/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Mamíferos/metabolismo , Camundongos , Neurregulinas/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Microambiente Tumoral
12.
Nat Commun ; 13(1): 5120, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-36045135

RESUMO

Binding of precursor tRNAs (ptRNAs) by bacterial ribonuclease P (RNase P) involves an encounter complex (ES) that isomerizes to a catalytic conformation (ES*). However, the structures of intermediates and the conformational changes that occur during binding are poorly understood. Here, we show that pairing between the 5' leader and 3'RCCA extending the acceptor stem of ptRNA inhibits ES* formation. Cryo-electron microscopy single particle analysis reveals a dynamic enzyme that becomes ordered upon formation of ES* in which extended acceptor stem pairing is unwound. Comparisons of structures with alternative ptRNAs reveals that once unwinding is completed RNase P primarily uses stacking interactions and shape complementarity to accommodate alternative sequences at its cleavage site. Our study reveals active site interactions and conformational changes that drive molecular recognition by RNase P and lays the foundation for understanding how binding interactions are linked to helix unwinding and catalysis.


Assuntos
RNA Catalítico , Ribonuclease P , Catálise , Microscopia Crioeletrônica , Conformação de Ácido Nucleico , Precursores de RNA/metabolismo , RNA Catalítico/metabolismo , RNA de Transferência/metabolismo , Ribonuclease P/metabolismo , Especificidade por Substrato
13.
Genome Biol ; 23(1): 118, 2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35585605

RESUMO

BACKGROUND: Spatial transcriptomics are a set of new technologies that profile gene expression on tissues with spatial localization information. With technological advances, recent spatial transcriptomics data are often in the form of sparse counts with an excessive amount of zero values. RESULTS: We perform a comprehensive analysis on 20 spatial transcriptomics datasets collected from 11 distinct technologies to characterize the distributional properties of the expression count data and understand the statistical nature of the zero values. Across datasets, we show that a substantial fraction of genes displays overdispersion and/or zero inflation that cannot be accounted for by a Poisson model, with genes displaying overdispersion substantially overlapped with genes displaying zero inflation. In addition, we find that either the Poisson or the negative binomial model is sufficient for modeling the majority of genes across most spatial transcriptomics technologies. We further show major sources of overdispersion and zero inflation in spatial transcriptomics including gene expression heterogeneity across tissue locations and spatial distribution of cell types. In particular, when we focus on a relatively homogeneous set of tissue locations or control for cell type compositions, the number of detected overdispersed and/or zero-inflated genes is substantially reduced, and a simple Poisson model is often sufficient to fit the gene expression data there. CONCLUSIONS: Our study provides the first comprehensive evidence that excessive zeros in spatial transcriptomics are not due to zero inflation, supporting the use of count models without a zero inflation component for modeling spatial transcriptomics.


Assuntos
Modelos Estatísticos , Transcriptoma
14.
Front Psychol ; 13: 809722, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35360593

RESUMO

This study investigates the phonological development of Mandarin voiceless affricates produced by Mandarin-speaking children. Thirty-six monolingual Mandarin-speaking children and twelve adults participated in a speech production task. Auditory-based transcription analysis and acoustic analysis were utilized to quantify the relative order of affricate acquisition. Both methods yielded earlier acquisition of alveopalatal affricates at age three than retroflex and alveolar affricates, whereas they differed in the acquisition order of retroflex and alveolar affricates. The former revealed that both retroflex and alveolar affricates were acquired at age five, regardless of aspiration, while the latter yielded earlier acquisition of retroflex than alveolar affricates. Possible reasons for the discrepancy are discussed in relation to the different nature of the two methods. Overall, the observed acquisition order of Mandarin voiceless affricates suggests that child speech development is a complex process, and is influenced by various factors including oromotor maturation and language-specific phoneme frequencies in the ambient language.

15.
BMC Bioinformatics ; 23(Suppl 1): 29, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35012449

RESUMO

BACKGROUND: DNA methylation has long been known as an epigenetic gene silencing mechanism. For a motivating example, the methylomes of cancer and non-cancer cells show a number of methylation differences, indicating that certain features characteristics of cancer cells may be related to methylation characteristics. Robust methods for detecting differentially methylated regions (DMRs) could help scientists narrow down genome regions and even find biologically important regions. Although some statistical methods were developed for detecting DMR, there is no default or strongest method. Fisher's exact test is direct, but not suitable for data with multiple replications, while regression-based methods usually come with a large number of assumptions. More complicated methods have been proposed, but those methods are often difficult to interpret. RESULTS: In this paper, we propose a three-step nonparametric kernel smoothing method that is both flexible and straightforward to implement and interpret. The proposed method relies on local quadratic fitting to find the set of equilibrium points (points at which the first derivative is 0) and the corresponding set of confidence windows. Potential regions are further refined using biological criteria, and finally selected based on a Bonferroni adjusted t-test cutoff. Using a comparison of three senescent and three proliferating cell lines to illustrate our method, we were able to identify a total of 1077 DMRs on chromosome 21. CONCLUSIONS: We proposed a completely nonparametric, statistically straightforward, and interpretable method for detecting differentially methylated regions. Compared with existing methods, the non-reliance on model assumptions and the straightforward nature of our method makes it one competitive alternative to the existing statistical methods for defining DMRs.


Assuntos
Metilação de DNA , Genoma , Ilhas de CpG , Entropia , Epigênese Genética
16.
J Speech Lang Hear Res ; 65(1): 53-69, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34860571

RESUMO

PURPOSE: Individuals with congenital amusia exhibit degraded speech perception. This study examined whether adult Chinese Mandarin listeners with amusia were still able to extract the statistical regularities of Mandarin speech sounds, despite their degraded speech perception. METHOD: Using the gating paradigm with monosyllabic syllable-tone words, we tested 19 Mandarin-speaking amusics and 19 musically intact controls. Listeners heard increasingly longer fragments of the acoustic signal across eight duration-blocked gates. The stimuli varied in syllable token frequency and syllable-tone co-occurrence probability. The correct syllable-tone word, correct syllable-only, correct tone-only, and correct syllable-incorrect tone responses were compared respectively between the two groups using mixed-effects models. RESULTS: Amusics were less accurate than controls in terms of the correct word, correct syllable-only, and correct tone-only responses. Amusics, however, showed consistent patterns of top-down processing, as indicated by more accurate responses to high-frequency syllables, high-probability tones, and tone errors all in manners similar to those of the control listeners. CONCLUSIONS: Amusics are able to learn syllable and tone statistical regularities from the language input. This extends previous work by showing that amusics can track phonological segment and pitch cues despite their degraded speech perception. The observed speech deficits in amusics are therefore not due to an abnormal statistical learning mechanism. These results support rehabilitation programs aimed at improving amusics' sensitivity to pitch.


Assuntos
Transtornos da Percepção Auditiva , Percepção da Fala , Estimulação Acústica , Adulto , Humanos , Idioma , Fonética , Percepção da Altura Sonora , Percepção da Fala/fisiologia
17.
Front Psychol ; 12: 693366, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34354636

RESUMO

This study investigated the developmental trajectories of categorical perception (CP) of segments (i.e., stops) and suprasegments (i.e., lexical tones) in an attempt to examine the perceptual development of phonological categories and whether CP of suprasegments develops in parallel with that of segments. Forty-seven Mandarin-speaking monolingual preschoolers aged four to six years old, and fourteen adults completed both identification and discrimination tasks of the Tone 1-2 continuum and the /pa/-/pha/ continuum. Results revealed that children could perceive both lexical tones and aspiration of stops in a categorical manner by age four. The boundary position did not depend on age, with children having similar positions to adults regardless of speech continuum types. The boundary width, on the other hand, reached the adult-like level at age six for lexical tones, but not for stops. In addition, the within-category discrimination score did not differ significantly between children and adults for both continua. The between-category discrimination score improved with age and achieved the adult-like level at age five for lexical tones, but still not for stops even at age six. It suggests that the fine-grained perception of phonological categories is a protracted process, and the improvement and varying timeline of the development of segments and suprasegments are discussed in relation to statistical learning of the regularities of speech sounds in ambient language, ongoing maturation of perceptual systems, the memory mechanism underlying perceptual learning, and the intrinsic nature of speech elements.

18.
Genome Biol ; 22(1): 184, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34154649

RESUMO

Spatial transcriptomic studies are becoming increasingly common and large, posing important statistical and computational challenges for many analytic tasks. Here, we present SPARK-X, a non-parametric method for rapid and effective detection of spatially expressed genes in large spatial transcriptomic studies. SPARK-X not only produces effective type I error control and high power but also brings orders of magnitude computational savings. We apply SPARK-X to analyze three large datasets, one of which is only analyzable by SPARK-X. In these data, SPARK-X identifies many spatially expressed genes including those that are spatially expressed within the same cell type, revealing new biological insights.


Assuntos
Algoritmos , Modelos de Interação Espacial , Neoplasias Ovarianas/genética , Transcriptoma , Animais , Cerebelo/anatomia & histologia , Cerebelo/metabolismo , Simulação por Computador , Conjuntos de Dados como Assunto , Feminino , Regulação da Expressão Gênica , Humanos , Camundongos , Bulbo Olfatório/anatomia & histologia , Bulbo Olfatório/metabolismo , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Célula Única
19.
Front Psychol ; 12: 611189, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33790832

RESUMO

Music impacting on speech processing is vividly evidenced in most reports involving professional musicians, while the question of whether the facilitative effects of music are limited to experts or may extend to amateurs remains to be resolved. Previous research has suggested that analogous to language experience, musicianship also modulates lexical tone perception but the influence of amateur musical experience in adulthood is poorly understood. Furthermore, little is known about how acoustic information and phonological information of lexical tones are processed by amateur musicians. This study aimed to provide neural evidence of cortical plasticity by examining categorical perception of lexical tones in Chinese adults with amateur musical experience relative to the non-musician counterparts. Fifteen adult Chinese amateur musicians and an equal number of non-musicians participated in an event-related potential (ERP) experiment. Their mismatch negativities (MMNs) to lexical tones from Mandarin Tone 2-Tone 4 continuum and non-speech tone analogs were measured. It was hypothesized that amateur musicians would exhibit different MMNs to their non-musician counterparts in processing two aspects of information in lexical tones. Results showed that the MMN mean amplitude evoked by within-category deviants was significantly larger for amateur musicians than non-musicians regardless of speech or non-speech condition. This implies the strengthened processing of acoustic information by adult amateur musicians without the need of focused attention, as the detection of subtle acoustic nuances of pitch was measurably improved. In addition, the MMN peak latency elicited by across-category deviants was significantly shorter than that by within-category deviants for both groups, indicative of the earlier processing of phonological information than acoustic information of lexical tones at the pre-attentive stage. The results mentioned above suggest that cortical plasticity can still be induced in adulthood, hence non-musicians should be defined more strictly than before. Besides, the current study enlarges the population demonstrating the beneficial effects of musical experience on perceptual and cognitive functions, namely, the effects of enhanced speech processing from music are not confined to a small group of experts but extend to a large population of amateurs.

20.
Front Cell Dev Biol ; 9: 636291, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33732704

RESUMO

Kashin-Beck disease (KBD) is a degenerative osteoarticular disorder, and displays the significant differences with osteoarthritis (OA) regarding the etiology and molecular changes in articular cartilage. However, the underlying dysfunctions of molecular mechanisms in KBD and OA remain unclear. Here, we primarily performed the various genome-wide differential methylation analyses to reveal the distinct differentially methylated regions (DMRs) in conjunction with corresponding differentially methylated genes (DMGs), and enriched functional pathways in KBD and OA. We identified a total of 131 DMRs in KBD vs. Control, and 58 DMRs in OA vs. Controls, and the results demonstrate that many interesting DMRs are linked to DMGs, such as SMOC2 and HOXD3, which are all key genes to regulate cartilage/skeletal physiologic and pathologic process, and are further enriched in skeletal system and limb-associated pathways. Our DMR analysis indicates that KBD-associated DMRs has higher proportion than OA-associated DMRs in gene body regions. KBD-associated DMGs were enriched in wounding and coagulation-related functional pathways that may be stimulated by trace elements. The identified molecular features provide novel clues for understanding the pathogenetic and therapeutic studies of both KBD and OA.

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